Oregon Revised Statutes Corporations and Partnerships § 65.347

(1) A director may at any time waive any notice required by this chapter, the articles of incorporation or bylaws. Except as provided in subsection (2) of this section, the waiver must be in writing, must be signed by the director entitled to the notice, must specify the meeting for which notice is waived and must be filed with the minutes or the corporate records.

(2) A director's attendance at or participation in a meeting waives any required notice to the director of the meeting unless the director, at the beginning of the meeting, or promptly upon the director's arrival, objects to holding the meeting or transacting business at the meeting and does not thereafter vote for or assent to any action taken at the meeting.